Sensitivity Determination And Control Of Paratrioza Sinica To Common Insecticides In Ningxia

The Paratrioza Sinica belongs to Hemiptera Psyllidae,and is distributed in the production areas of Lycium barbarum in China,which is one of the main and frequent obligate pests of L.barbarum.In order to clarify the sensitivity of P.Sinica to common insecticides in Ningxia,the indoor virulence of nymphs and adults of P.Sinica were determined by 7 kinds of insecticides in 4 categories respectively,and the sensitivity was evaluated by the relative virulence index among the insecticides in this study.In order to effectively prevent and control P.Sinica in L.barbarum production,5 new insecticides were selected to toxicity measurement and field efficacy trial of P.Sinica adults.Besides,the residue digestion dynamics of cyantraniliprole in fresh and dry L.barbarum fruits were studied to find out the half-life of the tested agent in L.barbarum fruit.Finally,a relative sensitivity baseline was established and the resistance was analyzed.The main results are as follows:1.The sensitivity of 3 nymph populations and 4 adult populations of P.Sinica in Ningxia to seven insecticides in four categories were studied by insect-immersion method and micro-drop method.The results showed that the nymph populations of P.Sinica in Yinchuan and Tongxin had higher sensitivity to seven insecticides,while Zhongwei population had lower sensitivity to seven insecticides.Yinchuan population was the most sensitive to abamectin and the least sensitive to lambda-cyhalothrin;the relative toxicity indexes of Zhongwei population to seven insecticides were all lower than 10;the sensitivity of Tongxin populations to imidacloprid,acetamiprid and abamectin was high,and the sensitivity to beta-cypermethrin and lambda-cyhalothrin in pyrethroid insecticides was the lowest.The adult population of P.Sinica in Qingshuihe and Hongwushan areas of Zhongning had higher sensitivity to seven insecticides,followed by Tongxin,Zhongning Hongliugou and Yinchuan areas.The adult population of P.Sinica in Zhongwei had the lowest sensitivity to seven insecticides.Yinchuan population was the most sensitive to acetamiprid and the lowest sensitive to chlorpyrifos and thiamethoxam;the relative toxicity indexes of Zhongwei population to seven insecticides were all lower than 20;the population of Zhongning Hongliugou area were most sensitive to imidacloprid,and had the lowest sensitivity to chlorpyrifos and abamectin.The population of Qingshuihe and Hongwushan areas had higher sensitivity to imidacloprid and lower sensitivity to abamectin.The population of Tongxin area had highly sensitive to abamectin and the lowest sensitivity to beta-cypermethrin in pyrethroid insecticides.2.The indoor toxicity of 5 new insecticides to the adults of P.Sinica was determined.The results showed that the order of toxicity of the five new insecticides was afidopyropen>cyantraniliprole>flonicamid>sulfoxaflor>spirotetrama ethyl ester.The results of field control showed that the control effect of afidopyropen against the adults of P.Sinica was the best one day after application,but only 61.79%.With the extension of time after application,the control effect of each agent increased gradually.7 days after application,the control effect of afidopyropen,flonicamid,sulfoxaflor,spirotetrama,cyantraniliprole were 94.11%,90.99%,95.91%,94.29%,97.45%.The above five new insecticides have good toxic effect on the adults of P.Sinica,and significant persistence,so that they can be used as rotation agents for the control of P.Sinica in production.3.A new insecticide,cyantraniliprole,was selected to carry out the residue digestion dynamic test in L.barbarum fruit.The results showed that after the treatment of cyantraniliprole 100 mg/kg,the digestion dynamic law accorded with the first-order kinetic equation.The half-life were 4.33 d and 4.95 d in fresh and dry fruits respectively,and the digestion rate of cyantraniliprole in fresh and dry fruits reached more than 90%after 21 days,which showed that cyantraniliprole was an easily degradable agent in L.barbarum fruit.4.Taking the wild P.Sinica population as the relatively sensitive population,the sensitive baseline of 7 pesticides was established,and the drug resistance levels of nymphs and adults of P.Sinica in Ningxia were analyzed and evaluated.The results showed that nymphs had developed medium to very high level resistance to thiamethoxam,and the resistance multiple was 19.18～263.27 times;The resistance to beta-cypermethrin and lambda-cyhalothrin was medium to high,and the resistance multiples were 25.09～132.9 and 28.66～76.65.The resistance to acetamiprid was low to medium,and the resistance multiple was 5.18～27.16 times;It was relatively sensitive to imidacloprid and abamectin,with resistance multiples of 4.36～35.21 and 5.78～114.35 times.The resistance to chlorpyrifos was at a sensitive to low level,and the resistance multiple was 1.43～6.32 times.The adults of P.Sinica had a very high level of resistance to thiamethoxam,and the resistance multiple was 296～749.39 times;The resistance to avermectin was medium to very high,and the resistance multiple was 25.43～563.78 times.The resistance of P.Sinica to seven insecticides had obvious regionality.The most serious resistancewas Zhongwei,followed by Tongxin,while the population of Yinchuan was relatively low.